Apparatus for tempering needles.



No. 696,033, Patented Mar. 25,1902.

.1. Furman.

APPARATUS FUR TEMPEHING NEEDLES.

(Application led Dec. 8, 1000.) (No Model.)

llxllu 1 l n uw@ Uirnn STATES ATENT FFICE.

JOHANN FUNKEN, OF AACHEN, GERMANY.

APPARATUS FOR TEMPERING NEEDLES.

SPECIFICATION forming part of Letters Patent No. 696,033, dated March25, 1902 Application filed December 8, 1900. Serial No. 39,203. (Nomodel.)

T0 @ZZ whom it may concern;

Be itknown that I, JOHANN FUNKEN, asubject of the Emperor of Germany,residing at No.1() Johanniterstrasse, Aachen, in the Empire of Germany,have invented a new and useful Improvement in Apparatus for TemperingNeedles, of which the followingr is a specification.

The present invention relates to the proccss which has for its objectthe hardening of sewing and sewing-machine needles and the like. It iswell known that these articles are tempered, such an operation beingessential to the manufacture; but the difficulty arises that needles andsimilar steel articles tend to become crooked in the hardening, whichnecessitates each one being straightened by hand afterward. This hashitherto been regarded as a necessary evil, and all attempts to preventthe needles becoming crooked in the hardening have failed and led to noresult. The present invention is a device for preventing this defect.

I start with the considerationthat the needles become crooked by beingtaken red-hot out of the hardening-furnace and suddenly plunged into thecold-oil and that this causes the distortion of the needles. This hasbeen ascertained by experiments. In order to ohviate this and preventthe needles becoming crooked, the apparatus herein described does notallow the red-hot needles to be cooled suddenly, but effects the coolingfrom red heat to ordinary temperature uniformly. The redhot articles arefirst passed through heated oil and are then dropped into thehardening-A oil.

The apparatus is illustrated in the accompanying drawings in Figures 1,2, and 3.

Fig. l is a longitudinal section. Fig. 2 is a transverse section, andFig. 3 a View from above.

At some height above the reservoir l, filled with hardening-oil, issuspended from the ceiling of the room a vessel 2, which has at thebottom of the side turned toward the center of the reservoir lhorizontal slots 3, 4, and 5. These can be opened or shut by means of aninside damper G. The inclined channel 7, separated from the vessel 2 bya space, rests at some distance from the upper edge of the reservoir,which channel, closed at both ends,

has at the lowest end a Waste-pipe 3, which passes into a boiler 9, inwhich oil can be heated by means of a heating device 10, placedunderneath. The suction-pipe l1 of a pump l2 also opens into this boiler9, the outlet-pipe 14 of the pump discharging into the aforesaid vessel2. The oil heated in the boiler 9 by means of the heating device 10 cantherefore be pumped into the vessel 2, from whence it iiows in widesheets 13 through the slots 3, 4, and 5, Figs. 2 and 3, by drawing outthe slide G, and is caught by the channel 7 and conducted back again tothe boiler 9 through the waste-pipe S.

- The process of hardening is as follows: The oil when sufficientlyheated in the boiler 9 is pumped into the vessel 2 before each hardeningprocess. Before the needles or the like steel articles are taken in ared-hot condition, with the pan, out of the Vhardenin,f.,ffurnace thehot oil is pumped out of the boiler 9 into the vessel 2, the slots 3, 4,and 5 heilig covered by the slide 6. On drawing out the latter hot oilfiows out in Wide sheets 13 13 13 into the channel 7. The pan, with thered-hot articles, is now placed over these hot sheets of oil 13 andtippedin, so thatl the articles are first passed into it and then intothe cold hardening-oil.

It is obvious that the red-hot needles or the like cannot becomedistorted by first being dipped in the hot sheets ofoil 13 and then intothe cold oil in the reservoir 1, as they would if immediately placed inthe latter in a red-hot condition. The change from red heat to cold bypassing through the sheets of heated oil is effected gradually, andtherefore a sudden cooling of the needles does not take place.Consequently the needles do not become crooked, and the defects arisingtherefrom, which quite spoil the manufactured article, are therebyobviated.

What I claim ist 1. Apparatus for hardening needles in oil comprising anoil-reservoir, means for heating and supplying oil thereto, a hot-oiltank, slots in the lower part of said tank, an adjustable slide capableof regulating the iiow of oil through said slots, an inclined channeladapted to receive the heated oil from said tank and a storage-reservoirfor oil, substantially as set forth.

IOO

2. In apparatus for hardening needles in oil, the storage-reservoir l,the heating-tank 9, the burner l0 underneath said heatingtank, the feedvessel12 located above the said heating-tank and adapted to draw hot oilfrom it., the hot-oil tank 2 adapted to receive supply from the feedVessel 12, slots 3 and 4 in said tank 2, the slide 6 adapted to open o1'close said slots, the channel 7 receiving the outflow

